Indeed, increasing striatal BDNF levels via pharmacological or behavioral stimulation that induces Bdnf gene expression (Duan et al., 2003; Spires et al., 2004; Peng et al., 2008; Simmons et al., 2009) or by viral delivery (Cho et al., 2007), improves disease phenotypes in several HD mouse models. This evidence concerns the gene BDNF and Huntington disease.